Non-return valves



Feb. 12, 1963 c. BUTTERWORTH 3,077,205

NON-RETURN VALVES Filed Feb. 15, 1961 3 Sheets-Sheet 1 I ll- INVENTOR:

Clifford BuHer-wor'ih BY Feb. 12, 1963 c. BUTTERWORTH 3,077,205

NON-RETURN VALVES Filed Feb. 15, 1961 a Sheets-Sheet 2 INVENTORZ Clifford BuHerwori'h BY My... {W

A'H'orneys Feb. 12, 1963 c. BUTTERWORTH 3,077,205

NON-RETURN VALVES Filed Feb. 13, 1961 5 Sheets-Sheet 3 FIG.5.

INVENT'OR:

Cl ifford BuHerwm-fh BY W J'M AH'or'neys United States Patent Ofiice BfilZZbE Patented Feb. 12, 1963 3,tl77,2ii NON-RETURN VALVES Clifford butterworth, Roclnlale, England, assignor to P.

Frankenstein 8: ons (Manchester) Limited, a corporation of Great Britain Filed Feb. 13, 1%1, Ser. No. 89,215 4 Claims. (Cl. 137-525) This invention relates to non-return valves of the type which incorporates a rubber or other elastic element having a closure portion adapted to co-operate with a rigid seating in the valve body and an integral attachment portion which, when engaged with the latter, serves to position said closure portion in operative relation with said seating.

Valves of the type aforesaid are commonly associated with inflatable appliances, such as liferafts; for example, at an inflation point of such an appliance or to control the passage of the inflating medium from one compartment of the appliance to another. It is also customary to provide such valves at the suction and delivery points of a handpump used for topping-up an inflatable appliance or any compartment thereof with air to compensate for leakage or inadequate self-inflation of the same, or for sucking up, and ejecting overside, water from the interior of a liferaft which has become partially swamped through any cause.

in a well-known construction of non-return valve designed for mounting upon the flexible outer wall of an inflatable structure, the valve body is made of metal or hard plastic material, in the form of a shallow cup with an externallydhreaded tubular neck projecting from its fiat base, the flexible wall aforesaid being clamped between the cup base and a nut screwed on to the threaded neck.

The elastic valve element is stamped from thin rubber or other sheet to a dumbbell profile, one end thereof being apertured and passed over the neck of the valve body before the latter is secured in position, after which the stamping is folded at its waist portion and its other end pushed through a circumferential slot in the rim of the cup, so as to overlie the annular base thereof and to seal the opening of said neck when pressure is built up within the inflatable structure.

Usually a secondary seal is provided by a captive screwcap applied to the body neck and containing a rubber or like disc for engagement with the free end of the latter, into which is cemented a plain bush of soft rubber for snugly receiving the delivery spigot or tube of an inflating pump.

When applied to an inflatable structure which is intended to be rolled or folded for compact stowage, the known valve construction above described has the drawbacl; that the closure portion of the elastic element (which tends to hang clear of its seating when not under pressure) is readily trapped during the rolling or folding operation aforesaid and may thereby acquire a permanent set across the rim of its cup-like housing, such as will hamper its subsequent seating therein. Such seating may also be prevented or hindered by distortion of the elements closure portion as a result of its waist portion being forced against one end of the slot in the cup during the screwing of the nut upon the threaded neck aforesaid.

The chief object of the present invention is to provide, in or for a nonreturn valve of the type referred to, an improved construction of elastic element which is not subject to the above-mentioned drawbacks of the known element and which can be relied on to maintain contact with its seating, even in the absence of internal pressure, without the aid of any metallic spring liable to corrosion in the presence of moisture.

According to this invention, the improved elastic element is moulded with an annular attachment portion adapted to engage a corresponding surface of the valve body and a disc-like operative portion united to said attachment portion by means of angularly-spaced integral bars which urge it towards a position concentric with the latter but axially offset therefrom.

Preferably, the operative portion is smaller than the internal diameter of the annular attachment portion so that the connecting bars form divergent spokes which may be curved or inclined in a circumferential direction.

In the accompanying drawings:

FIG. 1 is a sectional side of a non-return valve incorporating the improved elastic element and mounted upon the flexible Wall of an inflatable structure for use in topping-up the same;

FIGS. 2 and 3 are plan and inverted plan views respectively, f the elastic element aforesaid;

FIG. 4 is a plan view of one end-plate of a manual air or water-pump provided with suction and delivery valves according to the present invention; and

FlG. 5 is a partial section on the line 55 of FIG. 4.

In the example illustrated in FIG. 1 the body it? of an external topping-up valve for a liferaft is moulded in cellulose acetate-butyrate, or any other suitable hard plastie, to a generally known form; i.e. that part of it which will lie within the inflatable chain er is a shallow cup 11 with a cylindrical rim l2 and a substantially flat annular base 13 from whose exterior springs a concentric threaded neck 14 adapted to project outwardly through a preformed hole in the flexible wall 15 of the chamber aforesaid.

To secure the valve body 16 upon such wall, the material of the latter is engaged between the cup base 13 and a moulded ring-nut 16 applied to the threaded neck 14, the opposing faces of the cup 11 and nut 16 being preferably formed with concentric ridges 1'7, 18 to ensure a fluid-tight joint. If desired, a soft rubber Washer 19 may be interposed between the cup base 13 and the chamber wall l5, which latter is usually reinforced around the hole therein by cementing an annular patch Zll to its exterior.

Within the cup-shaped part 11 of the valve body ll) is housed an elastic element 21 moulded from natural or synthetic rubber in the form of a hollow conical frustum which is closed at its smaller end and whose larger end has an outwardly-directed circumferential flange 22.

The walls of the moulded frustum are apertured at angularlyspaced positions so as to leave the solid disc 23 at its smaller end connected to the outwardly-directed flange 22 by a number of (say, four) relatively thin spokes 24 which are inclined at, say, 45 degrees in a circumferential direction (sec FIGS. 2 and 3).

The flange 22 forms an attachment portion whereby the elastic element 21 is located between a circumferential shoulder 25 in the body cup ii. and an overhanging moulded ring 2 6 which is subsequently bonded to the rim 1?. of the latter, the disc-like closure portion 23 of the elastic element 21 being then held by the connecting spokes 24 in light contact with the base 13 of the cup 11. The exposed surface of the retaining ring 26 may be rounded to obviate risk of damage to the adjacent part of the chamber 15 when the liferaft is rolled or folded for stowage.

Preferably, the cup base 13 is moulded with a raised seating 27 around its central opening 28, and there may be corresponding circumferential lips 2% 3i on the locating shoulder 25 and retaining ring 26, respectively, in which case the attachment portion 22 of the elastic element 21 may be moulded to a complementary T section.

The inclined spokes 24 connecting the attachment portion 22 of the elastic element 21 to the closure portion 23 thereof allow the latter readily to yield to fluid pressure created within the threaded neck 14, the resistance to such automatic opening of the valve being initially dependent upon the angle of inclination of such spokes and tending to diminish progressively with separation of the closure disc 25 from its seating 27.

The threaded neck 14 is hushed in known manner with soft rubber or the like as at 31 for snug accommodation of the delivery spigot or pipe or an inflating pump, but preferably the necks interior is formed, about mid- Way of its length, with a circumferential groove 32 adapted to receive a complementary ridge 3 moulded on ibush 31, the latter being thereby securely located without any need for cementing it in place.

Furthermore, the outer end of the bush 31 may be formed with a projecting lip 34 adapted to overlie the end of the threaded neck 14 and to make airtight engagement with the top of a detachable screw-cap 35 applied in known manner to such neck and conveniently held captive by a cord 36 therefrom to a tab 37 on the reinforcing patch 20.

This arrangement obviates the necessity for mounting a sealing disc of rubber within the cap 35, whose exterior may have a central boss 38 in which the cord 36 is anchored. In this connection, it is convenient to form the boss 38 with an axial hole 39 which does not extend to the interior of the cap 35, but terminates at a cross-hole 4d of larger diameter serving to accommodate a knot at the end of the cord 36.

In FIGS. 4 and 5, the invention is applied to the suction and delivery valves of a manual airor waterpump, whose cylinder end-plate 41 is formed with circular apertures 42, 43 of diilercnt diameter respectively surrounded by concentric walls 44, 45.

The wall 44 around the larger aperture 42 is of sufiicient internal diameter to snugly accommodate one of the elastic elements 21 previously described, the attachment portion 22 of such element resting upon an annular surface 46 around the aperture. A hollow suction fitting 47 is spigotally engaged within the interior of the wall 44 and cemented thereto so as to locate the elastic element 21, a seating 48 at the inner end of its base being engaged by the closure portion 23 of such element.

The wall 45 around the smaller aperture 43 is of reduced diameter, so that its edge will support the attachment portion 22 of a second elastic element 21 which is introduced in inverted condition and whose closure portion 23 co-operates with a seating 49 around the aperture 43. The elastic element 21 in this case is held in place by a cap-like delivery fitting 5d cemented around the exterior of the wall and having a projecting hollow spigot 51 adapted for engagement with a rubber bush in an inflation valve such as that previously described.

I claim:

1. A non-return valve comprising a body having a fiat valve seat, a fiat elastic valve adapted to be seated thereon, an annular member in a plane outside of and substantially parallel to the plane of said valve, means for clamping said member to said body along the periphery of said member, a plurality of angularly-spaced bars integral with and connecting said member and valve, said bars being inclined in a non-radial circumferential direction and being at an angle to the plane of said valve, whereby said bars are adapted to urge said valve towards a position concentric with said member.

2. A non-return valve according to claim 1, further characterised in that the operative portion of the elastic element is smaller than the internal diameter of its annular attachment portion so that the connecting bars form divergent spokes.

3. A non-return valve according to claim 1, and having a rigid body with a concentric wall around a seating engaged by the operative portion of the elastic element, further characterised in that the annular attachment portion of such element is engaged between a shoulder in, or the edge of, such wall and an overhanging fitting secured externally of the latter.

4. A non-return valve according to claim 1, further characterised in that the valve body comprising a hollow male member with an internal shoulder on which the seating is formed, and a complementary fem-ale member in which said male member is secured, the attachment portion of the elastic element being engaged between the inner end of said male member and an internal shoulder in said female member.

References Cited in the file of this patent UNITED STATES PATENTS 2,355,862 Harper Aug. 15, 1944 2,462,189 Hess Feb. 22, 1949 2,941,541 Peras June 21, 1960 FOREIGN PATENTS 751,289 Great Britain June 27, 1956 1,044,192 France June 17, 1953 

1. A NON-RETURN VALVE COMPRISING A BODY HAVING A FLAT VALVE SEAT, A FLAT ELASTIC VALVE ADAPTED TO BE SEATED THEREON, AN ANNULAR MEMBER IN A PLANE OUTSIDE OF AND SUBSTANTIALLY PARALLEL TO THE PLANE OF SAID VALVE, MEANS FOR CLAMPING SAID MEMBER TO SAID BODY ALONG THE PERIPHERY OF SAID MEMBER, A PLURALITY OF ANGULARLY-SPACED BARS INTEGRAL WITH AND CONNECTING SAID MEMBER AND VALVE, SAID BARS BEING INCLINED IN A NON-RADIAL CIRCUMFERENTIAL DIRECTION AND BEING AT AN ANGLE TO THE PLANE OF SAID VALVE, WHEREBY SAID BARS ARE ADAPTED TO URGE SAID VALVE TOWARDS A POSITION CONCENTRIC WITH SAID MEMBER. 